Pivot for adjustable fulcrum pliers



June 19, 1951 v w. c. KRESS 2,557,296

PIVOT FOR ADJUSTABLE FULCRUM PLIERS Filed Feb. 16, 1948 IN V EN TOR.

BZZ/L'W 6 Jaw @L/ F um Patented June 19, 1951 PIVOT FOR ADJUSTABLEFULCRUM PLIERS Willard C. Kress, Grand Island, N. Y., assignor to J. H.Williams & 00., Buffalo, N. Y.

Application February 16, 1948, Serial No. 8,581

' 4 Claims. 1

This invention relates to adjustable jaw pliers, sometimes also calledwater pump pliers. In pliers of this type the pivot or fulcrum securedto one of the hinged elements is adjustable at the crossing with, theother element along that element, to give the opposed clamping jawsbetween the elements a desired spacing when the jaws are parallel andthe handle ends are also about parallel. Adjustable fulcrums or pivotsfor this purpose are known, but in handling them the pivotal point ofcoupling is likely to shift unintentionally, which requires one to stopand reset them, thus causing annoyance and delay in the use of thepliers.

An object of this invention is to provide improved adjustable jawpliers, which will yieldingly, resist any change in any spacing orsetting of the clamping jaws, in which the fulcrum or pivot between thehinged elements may be easily, conveniently and quickly shifted alongone of those elements to vary the initial spacing between their opposedclamping jaws, and held against unintentional or accidental change fromany adjusted relation, which will have maximum strength, and which willbe relatively simple, compact, practical, durable and inexpensive.

Other objects and advantages will be apparent from the followingdescription of one embodiment of the invention and the novel featureswill be particularly pointed out hereinafter in the appended claims.

In the accompanying drawing:

Fig. 1 is a face elevation of a pair of pliers embodying this invention;

Fig. 2 is an edge elevation of the same;

Fig. 3 is a sectional elevation of a part of the same, the section beingtaken approximately along the line 3-3, Fig. 2, the hinged elementsbeing separated on the pivot to open the jaws into the position in whichthe normal spacing between the jaws may be changed; and

Fig. 4 is a sectional elevation through the pivotal coupling between thehinged elements, and on a larger scale, to illustrate one form of detentthat may be employed.

In the illustrated embodiment of the invention, the pliers have a pairof metal crossing elements I, and 2 which are pivotally coupled orhinged together by a metal pivot or fulcrum member 3, which convenientlymay be a bolt that passes through the elements at their crossings. Themember 3 holds the elements I and 2 together during their hingedmovements. One pair of corresponding ends 4 and 5 of the elements haveopposed clamping jaws 6 and I, and

2, the opposite or other pair of ends are suitably formed to serve ashandles 8 and 9, which are generally parallel to each other but spacedsomewhat apart when the jaws are parallel to each other, as shown inFig. 1.

One-of these elements, such as element l is, provided, at the zone ofcrossing with the other element, with a plurality of slightlyintersecting,

cylindrical apertures H] of equal size and extending from face to faceof that element and arranged in a row extending in a, direction legthwise of that part of the, element in which they are provided. The.openings l l at the intersections between adjacent apertures H1 havediameters considerably less than the, diameters of the apertures [0 soas to provide restricted passages connecting adjacent apertures.

The shank of the bolt or pivot member 3, in the portion thereof whichpasses through any of the apertures ID was initially cylindrical but hasits opposite sides cut 01f to provide flat, parallel faces I2 and [3.which extend between and connect the convex end bearing surfaces.

M, that having a common center of curvature, the resultant shape of thispart being an interior segment of a cylinder. The diameter between theconvex surfaces I4. is slightly less than the diameter of each of theapertures II], so as to have a rotary bearing in any aperture 10. The.thickness of the segment, which is the distance between faces I2 and [3,is slightly less than the diameter or distance across the intersectionopenings or passages ll between apertures H1,

The bolt 3 is fixed at its head in element 2 in any suitable manner, sothat it will not rotate thereon. It is so fixed that when the handles 8and 9 are approximately parallel, as shown in Fig. 1, the flat surfacesl2 and [3 will be crosswise of the length of the slot formed by the rowof apertures, and convex surfaces IA of bolt or fulcrum 3 will haverotary bearing in the aperture 10 through which it passes. This preventsmovement of member 3, out of the aperture along; the slot. When the.handles are swun r apart. as shown in Fig. 3, the flat faces l2 and I3will be parallel with the length of the slot and can pass from apertureto aperture to adjust the pivot or fulcrum and thus space the clampingjaws 4 and 5.

A spring pressed ball detent unit 15 is recessed into one of the fiatfaces, such as face I! (see Fig. 4) with the ball l6 thereof projectinga little outwardly beyond face l2. A flange til at the outer end of therecess restrains ball [6' from ejection from the recess l'8; by acompressed member 3 keep the elements I and 2 coupled together.

It will be observed that one may, by using some force, shift the fulcrummember 3 from aperture to aperture to space the clamping jaws when thejaws are fully opened, yet when the jaws are in normal, workingpositions, the shifting of the fulcrum member 3 is impossible. Thespring detent prevents accidental or unintentional shifting of themember 3. The pivotal coupling between the elements is very simple,compact, strong, and easily manipulated.

It will be understood that various changes in the details, shapes,materials and arrangements of parts, which have been herein describedand illustrated in order to explain the nature of the invention, may bemade by those skilled in the art within the principle and scope of theinvention as explained in the appended claims.

I claim:

1. A pair of adjustable jaw pliers comprising a pair of elementscrossing each other intermediate of their ends, one pair ofcorresponding ends being formed with cooperating, opposed clamping jawsand the other pair of ends being formed as handles, one of said elementshaving, intermediate of its ends and at the crossing by the otherelement, a plurality of spaced apart, equal size apertures from face toface, connected by passages of considerably lesser width than theaperture diameters, and arranged in a row extending in a directionlengthwise of that portion of that element in which they are located,the other of said elements having an aperture in the portion thatcrosses said one element, and a pivot member passing through said lastnamed aperture and one of the apertures in said row and pivotallyconnecting said elements and holding them against separation, theperiphery of that portion of said member which passes through said oneelement having diametrically opposite convex bearing surfaces with acommon center of curvature and separated by diametrically opposite fiatsurfaces, the distance between said flat surfaces being slightly lessthan the width of each of said passages, and said convex surfaces havingrotary bearing in any aperture of the row through which it passes, and aspringpressed, ball detent recessed into one of said flat surfaces withits ball projecting from that fiat surface a distance from the oppositeflat surface greater than the width of each of said passages to normallyresist movement of said pivot member through the adjacent passages fromaperture to aperture in said row when said flat surfaces are parallel tothe length of said row, but yielding under pressure that depresses saidball until the member passes from one aperture to another in said row.

2. A pair of adjustable jaw pliers comprising a pair of elementscrossing each other intermediate of their ends, one pair ofcorresponding ends being formed with cooperating, opposed clamping jawsand the other pair of ends being formed as handles, one of said elementshaving, intermediate of its ends and at the crossing by 4 the otherelement, a plurality of slightly intersecting, equal size, cylindricalapertures arranged in a row extending in a direction lengthwise of thatportion of that element in which they are provided, the other of saidelements having an aperture in the portion that crosses said oneelement, a pivot member passing through alined apertures in saidelements at their crossing, pivotally connecting them and confining themfrom separation, the portion of said member which passes through saidone element having the shape of a cylinder segment with diametricallyopposite fiat faces separated a distance slightly less than the openingsat the intersections between adjacent apertures in said row, theopposite cylindrical surfaces of the segment having a 1'0- tary bearingin any apertures of the row through which it passes, and aspring-pressed ball detent recessed in one of said fiat faces with theball projecting from that fiat face until it yieldingly resists movementof the member through any opening between intersecting apertures whenthe flat faces are approximately parallel to the length of the row, butyielding under pressure to permit movement of said member from apertureto aperture in the row.

3. A pair of adjustable jaw pliers comprising a pair or elementscrossing each other intermediate of their ends, one pair ofcorresponding ends being formed with cooperating, opposing clamping jawsand the other pair of ends being formed as handles, one of said elementshaving, intermediate of its ends and at the crossing by the otherelement, a plurality of slightly intersecting, equal size, cylindricalapertures arranged in a row extending in a direction lengthwise of thatportion of that element in which they are provided, the other of saidelements having an aperture in the portion that crosses said oneelement, a pivot member passing through alined apertures in saidelements at their crossing, pivotally connecting them and confining themfrom separation, the portion of said member which passes through saidone element having the shape of a cylinder segment with diametricallyopposite flat faces separated a distance slightly less than the openingsat the intersections between adjacent apertures in said row, theopposite cylindrical surfaces of the segment having a rotary bearing inany aperture of the row through which it passes, a detent movable intoand partially out of said member through one of said flat faces and whenpartially out increasing the effective thickness from face to face untilit is greater than the opening of the intersection between adjacentapertures in the row, and a spring part urging said detent in an outwarddirection.

4. A pair of adjustable jaw pliers comprising a pair of elementscrossing each other intermediate of their ends, one pair ofcorresponding ends bein formed with cooperating, opposed clamping jawsand the other pair of ends being formed as handles, one of said elementshaving,

intermediate of its ends and at the crossing bythe other element, aplurality of slightly intersecting, equal size, cylindrical aperturesarranged in a row extending in a direction lengthwise of that portion ofthat element in which they are provided, the other of said elementshaving an aperture in the portion that crosses said one element, a pivotmember passing through alined apertures in said elements at theircrossing, pivotally connecting them and. confining them from separation,the portion of of said row.

WILLARD C. KRESS.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 548,006 McCauley et al. Oct. 15,1895 1,763,527 Jones June 10, 1930 FOREIGN PATENTS Number Country Date10,112 Great Britain Apr. 29, 1912 362,166 Great Britain Dec. 3, 1931839,175 France Dec. 26, 1938

